Myths vs facts: Magnesium and sleep

Magnesium is frequently marketed as a natural sleep aid, but the scientific evidence is mixed. Some studies indicate that magnesium can improve sleep quality in individuals with a confirmed deficiency, primarily by enhancing GABA activity and reducing cortisol levels. In people without deficiency, the effects are usually small or non-significant. Meta-analyses show a moderate improvement in subjective sleep quality, but objective measures like sleep onset latency or total sleep time often remain unchanged. Importantly, magnesium supplements are not a substitute for proper sleep hygiene or treatment of sleep disorders such as insomnia. High doses can cause diarrhea or gastrointestinal discomfort. The evidence level is 'mixed': there are mechanistic and some clinical hints, but no strong recommendation for the general population. Consumers should look for tested quality and consult a physician before taking high-dose supplements.